Related:

The legal battle over the cross began in 1989 and has become the longest running case ever over the meaning of the establishment clause.

Supporters had argued the 29-foot tall cross that sits atop a 14-foot base was one element in the larger war memorial at the site. Encircling the cross are some 3,000 plaques honoring military veterans, and the site is an official war memorial.

Opponents had contended that a Latin cross is the preeminent symbol of Christianity and amounts to an impermissible religious symbol on public property.

The Supreme Court made two major rulings in 2005 dealing with religious symbols on public land. In one case, the court allowed a Ten Commandment display to remain in the Texas Capitol, saying it was part of a larger display that had a primarily secular purpose.

In a second case, the court said a Ten Commandment display in a Kentucky courthouse had to go because its purpose was to send a religious message.

Since then, two other cross cases have come before the court. In 2010, the court ruled 5-4 that a cross atop a hill in the Mojave National Preserve in the California desert could remain.

In 2011, the court declined to take a case dealing with memorial crosses placed along a Utah highway to honor law enforcement officers who had died in the line of duty. A lower court had said the crosses were unconstitutional.

Steinberg, the law school professor, said if the Mount Soledad cross site is modified, it’s hard to know what changes would make it constitutional.

He said a cross that’s been allowed to remain on government land involves a memorial at the Army’s U.S. Military Academy at West Point. It also features an eagle perched on a shield and a large statue of Maj. Gen. John Sedgwick, who led Union Army troops in the Civil War.

“A reasonable person could assume that you could make a copy of the monument to Sedgwick and put it on Mount Soledad, then it would be constitutional,” Steinberg said. “But that might not be the case.”

A more prudent option, he said, would be to transfer the land where the cross sits to a private owner.

Glenn Smith, a professor at California Western School of Law in San Diego, said whether the land can be transferred directly to the memorial association — instead of putting it out for competitive bidding — has not fully been resolved.

“It is an open option, but it certainly isn’t what the 9th Circuit envisioned,” Smith said.